A Hong Kong newspaper says China has decided to start a corruption investigation into retired politician Zhou Yongkang, who until last year was one of the country's elite leaders.

The South China Morning Post on Friday said the decision to launch the investigation was confirmed by sources "familiar with the leadership thinking" of China's Communist Party.

The 70-year-old Zhou was a member of the elite Politburo Standing Committee, China's highest governing body, from 2007 to 2012. He also oversaw China's judicial system.

China's government has not commented on any investigation. If confirmed, it would be the first time in decades that the party has investigated economic crimes by a former or current Standing Committee member.

Zhou is also a close ally of disgraced former Politburo member Bo Xilai, who is awaiting a verdict in his trial last week for taking bribes, embezzlement and abuse of power.

The Communist Party has acknowledged widespread corruption within its ranks. It has made a highly publicized effort to crack down on graft, pursuing charges against several lower level officials.

But analysts say it is riskier for Beijing to go after senior officials, many of whom have reportedly used their leadership positions to amass huge amounts of wealth.

TheNew York Times reported last year that the family of former prime minister Wen Jiabao had accumulated $2.7 billion in hidden assets. China denied the story, calling it a "smear" with "ulterior motives."